In a two-sample Mendelian randomization analysis including 29 347 individuals, high N-terminal-pro-brain natriuretic peptide was associated with higher plasma adiponectin and the authors concluded that reverse causation potentially explained the adiponectin paradox in heart failure.43 Interestingly, observational sensitivity analyses in our study did not indicate the presence of reverse causation. Here, ADIPOQ is linked to heart failure.